A nuclear fuel assembly for light water reactor conventionally comprises a bundle of elongated fuel rods extending parallel to each other. In use, the fuel assembly is oriented vertically in a nuclear reactor core and a coolant fluid is caused to flow upwardly between the fuel rods.
Debris might be present in the coolant fluid and damage the fuel rods thus requiring removing or replacing the fuel assembly or damaged fuel rods. In a known manner, a debris trap or filter is placed upstream the bundle of fuel rods to trap debris.
EP 0 455 010 discloses a debris filter having a plurality of plates having a wave shape delimiting between them flow passages. The curvature of the passages allows trapping debris whilst limiting flow resistance of the debris filter.
Nevertheless, thin and short debris oriented perpendicular to the flow direction may pass through the filter and flexible longer elongated debris may also pass through the filter.